2001 F150 4.2L 2X4

I replaced the water pump on my F150 then when I cranked it up it sounded like it had a bad misfire and the p1309 and p0340 codes came up. If I disconnect the battery, hold down the break to drain the existing voltage, to reset the computer, the truck runs fine til I turn it off and crank it back up, which is when it starts misfiring again. I drove it 35 miles after a rest with no problems at all. It just seems to be there on the restart and stay til I reset the computer or if it shuts off on its own due to the misfire.
Any ideas of a fix?

Thanx,
l965mustang

 

Check the wiring to your cam position sensor. It might be unplugged or have a damaged harness/connector.

Steve

 

It's plugged in. I just need to know what kind of voltage I need to the green, black/white, red with KOEO (Key on, engine off).

 

BLK/WT is ground, RED is HOT (Batt Voltage) and the GR is the signal output to the PCM.

The output signal should be a 0V to 12V and back square wave, three complete cycles per crank revolution (or was it three per two, don't remember). You obviously have to rotate the engine to get this.

Steve

 

Thanks Steve,
I probed the wires and rotated the engine and I am getting pulsing (2-12v) from the green wire. I think that the shaft may be off a gear or two. I loosened the retainer bolt and turned the shaft 1/16" clockwise and the idle smoothed out but the truck still bucked when I got her out on the road. Turned it 1/8" ccw and rough idle and bucking on the road.

 

Did you have the cam position sensor/synchronizer assembly out of the engine when you did the water pump? If it's not lined up right you will get the P1309 and possibly the P0340. There is a special tool for lining it up.

 

Dave,
No I didn't have the syncronizer out. I said earlier that if I reset the computer by disconnecting the battery, the problem would cease, but that is not true. The only way that I can get it to stop is if it cuts off by itself due to the rough running or if I do a couple of short bursts of trying to start it without actually starting the engine. On the third burst, crank it up and it runs like a charm. Seems like the computer runs the engine in a different mode after I do that. I guess my only other option is to replace the syncronizer. What do you think?
Joe

 

Supposedly if the PCM doesn't see a good CMP signal when you crank it it will "fake" a reading and see if that works. When you give it short bursts it might be trying a reading and then on the 3rd try it sees one it likes so it runs ok. It's hard to explain properly.
I think I'd try replacing the CMP sensor and borrowing the tool to line it all up properly.

 

CMP sensor has been changed. Didn't fix the problem. I think it has to be the shaft itself or the alignment. I'll let you guys know after I find an alignment tool.
Thanks,
Joe

 

Apparently the guy I bought the truck from had messed with the sensor/synchronizer assembly and when he tightened it down, instead of going 54 degrees counter clockwise from the front of the engine, he had it turned 54 degrees clockwise. I turned it about 54 drgrees ccw from the front of the engine and the problem is gone.
Thanks for all of the help,
Joe

 

Good to hear that you got it figured out

 

Yeah, me too. I kinda baffles me that it would even run when it was turned 108 degrees in the wrong direction.
Take care,
Joe

 

For all that are looking for a synchronizer tool for the 4.2L and 3.0L ($29.95), here's a site:
etoolcart.c0m/index.asp?PageAction=VIEWPROD&ProdID=226

 

I couldn't send links since I am not a seasoned user so change the zero (0) in .c0m to an ohh (o) to get to the site.